Many consumer products employ software in order to provide a broader range of features at a given price than is possible using hardware alone. The Consumer Electronics marketplace is increasingly competitive and lowest price solutions have to be sought—for example storage provided for software programs must be both low cost and utilised in flexible ways to accommodate functional variations. In addition, products are becoming increasingly dependent on upgrading, for example to fix bugs or perhaps to offer customisation to the end user.
Software programs are typically stored in non-volatile memory within a product, for example Read Only Memory (ROM) this generally having a lower cost per unit memory size than other forms of non-volatile memory.
As standard ROM is non-reprogrammable, silicon manufacturers have developed a variety of electrically reprogrammable non-volatile memory devices to supplement ROM including EEPROM and Flash® RAM. These types of devices allow the original software in ROM to be updated in the field. A disadvantage of such technologies is their relatively high cost; it is therefore desirable to minimise the amount of such memory used in products.
A further typical drawback of field upgradable products is the requirement that the upgrade software code be configured to be compatible with the specific hardware of the product. This can result in the need for several versions of the same upgrade code, each configured for a particular product hardware platform.